Gallipolis is a chartered village in the U.S. state of Ohio and the county seat of Gallia County. The municipality is located in Southeast Ohio on the Ohio River. The population was 3,641 at the 2010 census. When the population dropped below 5,000, Gallipolis became a village, but continues to operate under its existing city charter.Gallipolis is the second-largest community in the Point Pleasant Micropolitan Statistical Area, which includes all of Gallia County, Ohio and Mason County, West Virginia.